Such a cooking apparatus is known from German Patent DE No. 35 03 576 C2.
For the stability of the ends of the glass envelope of an electric filament used in an electrical cooking apparatus as a source of IR radiation, it is necessary that those ends, at which the glass envelope is sealed onto current supply conductors to the filament, have a comparatively low temperature. The housing of the cooking unit therefore has openings, which are adapted to receive a respective end of the envelope.
However, in addition to producing IR radiation, the incandescent filament also produces a comparatively large quantity of light. A disadvantage of having the openings in the housing of the cooking unit, which receive the ends of the glass envelope, is that light emanates from the housing through these openings. This light causes disturbing light effects through the hot plate and moreover renders visible electrical and constructional parts, such as electrical cables.
According to the aforementioned German Patent Specification, this disadvantage is obviated in that a heat-resistant flexible light-screening first layer is provided on the side of the hot plate facing the cooking unit in a zone around the cooking unit and in that this layer and the remaining surface of the hot plate laterally of the cooking unit are covered by a heat-resistant opaque second layer. The said Patent Specification itself indicates extensively how stringent are the requirements which must be imposed on such means for influencing the light transmission of the hot plate.